Apparatus for handling and spraying coating material

ABSTRACT

A method and apparatus for mixing, transferring and spraying a cementitious coating material. The apparatus includes a main power source for driving a hydraulic pump, which drives hydraulically a first hydraulic motor for actuating an air pump, a second hydraulic motor for actuating a mixer, and a third and fourth hydraulic motor for actuating impeller pumps. Spray nozzle means are provided with electrical switch means for controlling the transfer of coating material to the nozzle by regulating a hydraulic solenoid valve circuitry between the hydraulic pump and the third and fourth hydraulic motor.

United States atet [72] Inventor Arvld W. Malm 2,758,945 8/1956 Widmayer 914 South 48, Tacoma, Wash. 98408 20.672 1/1958 Arce 259/151 [21] Appl. No. 73,368 3,107,901 10/1963 Zimmerman 259/147 [22] Fil d S 1 18,1970 3,424.438 1/1969 Knotts 259/151 [451 Patented 1971 Primary Examiner-Robert W. Jenkins Attorneys-Pasqual J. Ferra and Nicolaas De Vogel [54] APPARATUS FOR HANDLING AND SPRAYING COATING MATEFIAL ABSTRACT: A method and apparatus for mixing, transferring Chums 3 Drawmg Figs and spraying a cementitious coating material. The apparatus 52 us. (:1 259/147, includes a main Power source for driving a hydraulic p p 259/ 9 259/1 1 259/17 which drives hydraulically a first hydraulic motor for actuating [51 Int. Cl B284: /06 P p 3 Second hydraulic motor for mating a mlxerv I50] Fleld 01 Search 259/147. and a third and fourth hydraulic motor for ct ng impel er 161,69. 178. 162. I64, 165, 146, I48, 153 pumps. Spray nozzle means are provided with electrical switch means for controlling the transfer of coating material to the [56] References Cited nozzle by regulating a hydraulic solenoid valve circuitry UNITED STATES PATENTS between the hydraulic pump and the third and fourth hydrau- 2.700,535 1/1955 Harrington 259/151 F J 49 lk/fl 50 22 I I: Z I y a /45 l l l I :2: 0% /Z4 1 l 5'6 z 28 F /02 we W l I v V 3% M 5V /54 l 72 1 V #22 /2 as /42 5 V 74 32 r v #1 1 A22 3/ /2 M a0 PATENTEUuuv 23 l97| 3. 622 l 3 0 sum 1 or 2 INVENTOR. AKV/D W MALM APPARATUS FOR HANDLING AND SPRAYING COATING MATERIAL BACKGROUND OF THE INVENTION 1. Field of the Invention This invention pertains broadly to fluid-handling systems and dispensing apparatus and particularly to mobile apparatus-carrying a system for mixing, transferring and spraying a cementitious coating material via nozzle means onto walls, ceilings, or the like.

2. Description of the Prior Art In the modern building business the interior surfaces of walls and ceilings are covered with sound absorbing and insulating material rather than the old-fashioned hand-plastering material. Therefore, various systems have been designed by building subcontractors for spraying on a mixture which covers the walls and ceilings in an even and substantially smooth texture. For instance, the ceiling coating can be provided with sparkling bits of material so that a rough surface with sparkles, providing a modern and artistic impression, can be obtained. The mixture for walls is normally of a smoother texture and somewhat in the order of a stipple or orange peel finish.

The coating mixture is thus sprayed onto walls and ceilings for finishing the interior rooms of buildings; however, not only in new buildings, but also older homes, offices, and the like, can this type of material be sprayed in order to improve the interior appearance and acoustic qualities.

The art of spraying plaster or acoustic mixture onto walls and ceilings has only been developed over the past years and the apparatus used for accomplishing the spraying operation includes mixing machinery, air pumps, pressure pumps for transporting the material at a certain pressure and speed regulators. The existing systems so far in operation and on the market comprise various machineries having their own individual power sources and their operation has been cumbersome and very unreliable because of the various independent sources which must be relied upon. In addition, the controlling elements, gears, chains, clutches, etc. of the prior art apparatus are difficult to regulate and not in logical and immediate reach of the operator. It becomes in some apparatus particularly difficulty and awkward for an operator to control the supply of the mixture and the air while spraying a ceiling or wall.

Thus, when comparing existing systems with the present invention, it can be stated that the prior art apparatus are basically arrangements of a plurality of mechanical cooperating parts which form a "mechanical spray machine," while the operation and system of the present invention relies on one power source with a hydraulic controllable transfer system and for reasons of referral will be called hydraulic spray apparatus" hereinafter.

In general, the system for spraying comprises a mixing apparatus for mixing the coating material and a pump for pumping the mixed material to a nozzle where air and material under pressure are combined so that a spray is formed.

The mechanical spray machines are equipped with a twoor three-speed transmission on the pump drive. This narrows the variety of speeds available to the operator. The hydraulic spray apparatus presents a speed varying capability ranging from minimum to maximum by the indirect control of a relief valve in the hydraulic circuitry.

The mechanical spray machines are built with a gearing arrangement which prevents the operator from actuating the mixer and the spray pump simultaneously.

In the hydraulic spray apparatus, the mixer and pump can operate simultaneously, which provides for a constant wellbalanced spray mixture, so that an even spray finish is maintained during the entire operation. In addition, the hydraulic spray apparatus allows for independent mixer speed and pump speed so that overrnixing can be controlled.

Running the mixer while spraying is necessary at the end of the operation because the tank will be almost empty and the mixture clinging to the tank sides will be subsequently wiped by the mixer towards the transfer pump.

The mechanical spray machines have an air pump or compressor, which is directly driven by the main motor and thus operates also when not needed, for instance, during the mixing cycle, thereby causing extra drag and wear to the system. In addition, the mechanical spray machines need continuous maintenance, such as cleaning, oiling, greasing and adjusting because of the many exposed gears, chains, clutches, etc.

In the hydraulic spray apparatus the operating circuitry is sealed off from the dust and the cementitious material so that the above-mentioned maintenance is kept to a minimum and various projects can be accomplished without the maintenance time delay. In short, the advantages of the system and apparatus for spraying cementitious material over the prior art is impressive, not only in time savings, reliability and economics, but also in the final product, because its consistent texture is clearly visible and an improvement over sprayed-on coating applied by mechanical spray machines.

Since the combination of this apparatus, its unique arrangement as well as its method of operation is specifically designed to serve the trade of coating ceilings, walls, etc., which trade is relatively new in the building and interior decorating fields, there was no art found which appeared to be identical to the apparatus and system of the present invention as described and explained hereinafter.

SUMMARY OF THE INVENTION The concept of the invention lies mainly in providing mobile apparatus for mixing, transferring and spraying a plaster-type mixture onto walls and ceilings by using a reliable system of actuating means receiving its main power from one source and a regulating control circuitry which can be operated in an easy manner, thereby providing the operator with control of the coating material consistency and spraying speed.

It is therefore an object of the present invention to provide for an improved and simplified apparatus for mixing, transferring and applying a coating mixture onto walls and ceilings.

It is another object of the present invention to provide for an improved apparatus having a main power source for driving hydraulically various components independently or simultaneously with independent control for obtaining a desired mixed material having a balanced consistency.

It is a further object of the present invention to provide for an apparatus for mixing and maintaining agitated a quantity of coating material and for feeding such material under pressure via a hose line to an applicator nozzle having means for controlling discharge of air and material by electrically varying hydraulic fluid paths.

It is an additional object of the present invention to provide for a novel method of applying cementitious mixtures to walls and ceilings with less effort, less manpower, and greater speed than by current standard procedures.

Thus, the present invention provides for an apparatus for mixing, transferring and spraying a cementitious coating material, comprising in combination, a power source, a hydraulic pump means connected to the power source, an air pump compressor means having first hydraulic-motor-actuating means, a mixing means having second hydraulic-motor-actuating means, a transferring means having third hydraulicmotor-actuating means, and a hydraulic-fluid-carrying circuitry including bypass solenoid valve controlled circuitry interconnecting the hydraulic pump means with the first, second and third hydraulic motors. The apparatus employs in combination a noule means for spraying the coating material, and has a conduit means arranged between the air pump, the transfer means and the nozzle means for supplying the nozzle with the coating material and the air pump compressor means output, and furthermore, there is a switching means on the nozzle means electrically connected to the solenoid valve controlled circuitry for controlling the operation of the transfer means.

Other objects and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view of the preferred form of a mobile cementitious coating apparatus, in accordance with the present invention, mounted on a truck of conventional design.

FIG. 2 is a perspective view of the preferred form of a mobile cementitious coating apparatus, in accordance with the present invention, mounted on a trailer of conventional type.

FIG. 3 is a diagrammatic view of the circuitry in block form fashion which embodies the operating system of the cementitious coating apparatus.

DESCRIPTION OF THE INVENTION Referring now to the preferred embodiment of the present invention, there is illustrated in FIG. 1 a truck which carries a spray apparatus 12. The spray apparatus 12 includes various actuating means that are powered via a. hydraulic system 14 (shown in FIG. 3). The spray apparatus 12 envelops various large components which are arranged for mobility in order to transport the apparatus rapidly to wherever a coating project has to be accomplished. The truck 10 in FIG. 1 and the trailer 16 in FIG. 2 represent preferred arrangements, but it should be understood, however, that various other configurations or layouts can be employed without departing from the principle of the invention.

Observing now the various details, the truck 10 carries two tanks 18 and 20, each having, independently rotating, a set of mixer blades 22 and 24, respectively. Since like reference nu metals are used for identical components throughout the FIGURES, the tanks 18 and 20 on the trailer 16 in FIG. 2 and the tanks 18 and 20 which are schematically illustrated in FIG. 3, are therefore provided with the same numerals. Each tank has a different mixture; for instance, the tank 18 with the wiper blades 22 is used for mixing a wall-coating material and the other tank 20 with its wiper blades 24 is used for a ceilingcoating material. When the coating material is thoroughly mixed it can be transferred from the tanks 18 and 20+ by means of transfer means or worm screw pumps, such as stator tubes 26 and 28 or the like. Hoses or conduits 30 and 32 are used to channel the coating material to the nozzles 34 and 26 respectively. Conduit means 38 and 40 are used for connecting the nozzles 34 and 36 to a source of compressed air which is delivered by the air compressor or air pump 42. The nouies 34 and 36 are provided with an internal intersection for carrying the spray material and the compressed air together so that the particles of the mixed material are lifted away by the air velocity and thus a spray leaves the nozzle, which embodies a cone-shaped stream of finely divided spray material particles carried by the air. By holding the nozzles 34 or 36 at a predetermined distance from the wall or ceiling, an even coating of spraying can thus be applied.

A console 44 carrying a plurality of switches 46 and pressure indicators 48 and 50 for controlling the various components through the operation of the hydraulic system or circuitry 14 (shown in FIG. 3) is employed on the truck 10 or the trailer 16 and is positioned in easy reach of the operator.

The system of the hydraulic spray apparatus 12 receives its main power from one source which is a motor or the like. In the truck 10 the main power source is the truck engine 54 itself, which is geared in neutral by coupling to a transmission 56 which decouples the driving mechanism of the truck 10. The engine 54 thus may be coupled for rotary motion with a hydraulic pumping means 58.

In FIG. 2 the trailer 16 carries its own power source 60, which is coupled to the hydraulic pump 58 serving the same purpose as the pump 58 in the truck 10 or the hydraulic pumps 64 and 66 in the circuitry shown in FIG. 3.

In both mobile units the hydraulic pump 58 is arranged next to a hydraulic fluid tank 62 for pumping the contents or hydraulic fluid to various actuating motors, such as a first actuating motor 67 for driving the air compressor 42, a second hydraulic actuating motor 68 and if desired a third hydraulic actuating motor (not shown), for rotating the mixer blades 20 and 24 and a fourth and fifth hydraulic motor 72 and 74 for driving the stator tubes 26 and 28 interior screw blades.

In general, each mobile unit 10 or 16 delivers a mixed cementitious coating material, sometimes called slurry, via the hoses 30 and 32 to the nozzles 34 and 36. By experience, it has been found most practical to store the hoses carrying the air 38 and 40, respectively, onto a supporting means located at one side of the mobile unit 10 or 16. Because the sets of hoses are of considerable length, in order to reach into buildings from the outside, books 82 and 84 are used to wind the hoses various turns in a pretzellike configuration for storing.

The general arrangement of the main components forming the hydraulic spray apparatus 12 can be altered; however, the principle of operation and the control system of the spray apparatus 12 per circuitry 14 will remain substantially the same.

Referring now to FIG. 3 there is shown a motor 90, which could be a truck motor or an independent power source, as shown in FIG. 1 and 2, which motor drives a hydraulic pump means 64 and 66 directly or indirectly via a transmission means 68.

Here, again, it should be emphasized that the circuitry as ii lustrated in FIG. 3 is a practical, worked-out system which has been proven to operate most efficiently. However, it can be realized that instead of having two hydraulic pump means on a common axle, such as hydraulic pumps 64 and 66, that one hydraulic pump with one output will suffice and also that a transmission or coupler 68 might be eliminated.

Thus, the power source 90 drives the hydraulic pumps 64 and 66 via the rotating axle 92. Since the output of the hydraulic pump has to match the input of a hydraulic actuating motor, the circuitry of the hydraulic pump 64 is connected to a matched hydraulic actuating motor 67 and the same applies for the hydraulic pump 66 and its motors 68, 72 and 74. The hydraulic pumps 64 and 66 receive hydraulic oil from the reservoir 62 through an input line 100.

Referring now to the first part of the total circuitry 14 there is shown a pump 64 which pumps oil from the reservoir 62 under pressure through pipe 102 via a manual valve 104 and the hydraulic motor 66 back via return pipe 106 to the reservoir 62. The pipe 102 has a parallel branch 108 which carries a relief valve 110 which is served manually and upon opening will reduce the pressure of the hydraulic fluid in the pipe 102 and return a portion of the oil through the return line 112 back to the reservoir 62. Thus, when the relief valve 110 is open, the reduced pressure and gallons per minute through the hydraulic motor 67 will accordingly reduce the speed of the motor 67, which coupled to the compressor 42 will produce less air velocity or compression so that as a result the relief valve 110 is used for regulating or varying the air output through the air hoses 38 or 40 to its respective noules 34 and 36. The indicator 48 coupled to valve 110 will assist the operator in turning the p.s.i. of air pressure he requires.

The second and main part of the hydraulic circuitry 14 starts from the hydraulic pump 66 which will pump oil from the reservoir 62 under a predetermined pressure through pipe to an intersection or cross 122. From the cross 122 the oil may flow via the branches or pipes 124, 126 or 128.

Assuming that the oil flows via pipe 124 to the manually operated valve 130 which is in open position, then the hydraulic motor 68 will rotate the mixing blades 22 and 24 in the mixing tanks 18 and 20, respectively. A return line 132 will provide for return of the oil towards the tank 62. In case that the mixture is thoroughly stirred, the actuating motor 68 will be stopped by manually closing valve 130.

Observing now the cross 122, it will be noted that pipes 126 and 128 each are provided with a solenoid valve and 142 which are connected via an electronic circuitry 144 with switches 146 and 148 for automatically controlling the posi tion of the valves 140 and 142 in an opposite function. In other words, when valve 140 is closed, valve 142 will be open and when valve 142 is closed, valve 140 will be open, depending on the electrical activation of the electrical switches 146 and 148 provided at the nozzles 34 and 36, respectively. Assuming that the valve 140 is in an open position, then the oil will flow via the pipe 126 to a junction or pipes 150 and 152 carrying manual valves 154 and 156 for controlling the oil flow to the actuating motors 72 and 74. As explained, the actuating motors 72 and 74 drive the stator tube screws 26 and 28 and thus the mixed or stirred material will flow through the hoses 30 or 32 depending upon which manual valve 154 or 156 is opened. From the actuating motors 72 and 74 the oil returns via line 160 and line 162, respectively, to the reservoir or tank 62.

Also, from the cross 122 oil may travel through the pipe 128 via a relief valve 164 to the solenoid 142 back via a manual control valve 166 and return pipe 168 back to the reservoir 62. A return line 170 will assure return and oil loop continuance from pump 64 output to pump 64 input and line 170 thus serves as a heat preventing as well as a safety pressure line to the system. When the relief valve 164 is open, the pressure or the gallons per minute in the oil line 126 will be reduced provided valve 142 is closed and 140 is open, so that the speed of the actuator motors 70 and 74, respectively, is slowed down. In other words, adjustment of the valve 164 will vary the speed of the hydraulic actuating motors 72 and 74 and thus accordingly reduce the amount of mixture which is pumped by the stator tubes 26 or 28 toward the respective nozzles. Also, it could be stated that varying of the valve 164 will change the amount of mixture sprayed from the nozzle which can be regulated at will by the operator and per required amount by using the indicator means 50.

As explained, the norzles 34 and 36 are equipped with an electrical switch 146 and 148, each switch being connected in parallel with one another and via electrical circuit means 144 including an electrical power source 190, connected to the solenoid valves 140 and 142. Manipulation of either switch will thus open or close the solenoid valves 140 or 142 in an alternate or flip-flop manner.

Assuming that the operator will start a spray job, the first requirement will be to fill both tanks 18 and with a mix having the required proportion of ingredients. The operator has valve 104 closed and valve 110 open, and also has the valve 140 closed and 142 open. Thus, oil will freely circulate from the hydraulic pumps 64 and 66. The valve 130 will be open and thus the mixers 18 and 20 are operating. By opening the valve 104 and closing the valve 110 completely or partly, the air supply will be provided for. Thereafter the operator will use one of the nozzles and by switching electrically reverse the opened and closed position of valve 142 via 140, so that the stator tube 26 and 28 is actuated. As stated before, the adjustment of the relief valve 164 may vary the speed of the mixture units 18 or 20. When the mixture is completed, valve 166 is open and the valve 130 is closed and the air compressor valve 104 is open and regulated by the relief valve 110, so that the compressor valve 104 is open and regulated by the relief valve 110, so that the compressor delivers the right amount of air output. The switch 140 is still in a closed position and the valve 142 is still in its normal open position so that oil is always circulating via the loop which is provided from the pump 66 towards the cross 122 and the line 128 through the relief valve 164 through valve 142 and valve 166 via return line 168 back to the reservoir 62. The relief valve 110 with indicator 48 and manual flow control valve 104 controls the speed of the motor 67 which drives the compressor 42. The air from the compressor 42 is used to atomize with the cementitious coating material for obtaining the desired sprayed-on pattern. The air valves 184 and 186 are used to regulate the amount of air through the nozzles 34 and 36. Hydraulic pump 64 pumps oil via pipe 102 through valve 104 to hydraulic motor 67. in this circuitry there is a bypass valve 110. The bypass valve 110 is a pressuresetting valve and is used to set the amount of pressure on the line 102. Valve 104 is the valve to gauge the gallons per minute or the speed of the motor 67. By opening valve 104 the motor speed is increased and by closing the valve 104 the motor speed is decreased. The pressure on the bypass valve 110 indicator 48 must be set high enough to take care of the work load on the motor 67 or within the pressure limit of the motor 67 (the same is true for the bypass valve 164 and the components on that circuitry). If there is an excess of oil pumped, then the turning of valve 104 towards a closing position will slow the motor 67 and the oil will pass over the bypass valve 1 10 and back to the reservoir 62 via pipe 112. The gauge 48 tells the operator what the line pressure is. The speed of motor 67 can also be regulated by the bypass valve and minor air output regulations can be accurately regulated thereby. With both of the electric switches 146 and 148 in an off position the oil from pump 66 goes through pipe to pipe 128 through valve 164 and valve 142 and valve 166 and back to the reservoir 62. This situation occurs when no hydraulic components (motors) are being used and thus the oil is circulating back to the reservoir 62, at low pressure. If this type of circuitry or return loop were not built into the hydraulic system, the oil when not being used for work (running motors) would always be flowing over the bypass valve 164 causing excessive heat which breaks down the viscosity of the hydraulic oil and consequently would cause excessive wear.

To start the mixers l8 and 20 with both electric switches 146 and 148 in an off position (this means the solenoid 142 is in an open position and solenoid valve 140 is in a closed position) the following procedure is initiated. The operator opens valve (manual control valve) and closes valve 166 (both manual on" and off valves), the flow of oil to the reservoir 62 via valve 166 stops and the oil then flows through pipe 124 through open valve 130 to motor 68 and back to the reservoir 62 via pipe 132. Valve 130 controls the speed of the motor 68. If valve 130 is turned down to slow the motor the excess oil is passed over the bypass valve 164, through pipe 170 to the reservoir 62. The bypass valve 164 is set at a pressure high enough to do the job of mixing, within the pressure limits of the motor 68. The gauge 50 tells the operator the line pressure or the working pressure on the motor 68. The speed of motor 68 also can be regulated by the bypass valve 164. To stope the mixers l8 and 20 the operator opens valve 166 and turns off or closes valve 130. When the operator is mixing, the solenoid valve is closed, this prevents the oil from going to the pumps (26 and 28).

When the operator turns on one of the switches at the nozzle, then the solenoid valve 140 opens and solenoid valve 142 closes. Then the oil goes through lines 120 and 126 through solenoid valve 140 and to lines 150 and 152, depending on which pump is to be operated, by opening valve 154 or 156 (manual control valves). For example, when the operator opens valve 154, the oil flows to pump motor 72 and back to the reservoir 62 via the return pipe 160. Valve 154 controls the speed of motor 72 and valve 156 controls the speed of motor 72. Excess oil, due to the partial closing of the valves 154 or 156 is then passed back to the reservoir 62, over the bypass valve 164 through pipe 170. The speed of the pump motors can also be regulated by the bypass valve 164, which thus provides for a more accurate tuning of the system. To operate both the pump motor and the mixer motor, when the operator is spraying, the operator must open valve 130 which will provide for oil flow and actuation of the mixer motor 68. In general, the circuitry embodies all necessary precautions to keep oil circulating, prevent the heating of oil or parts and reduce wear.

Although I have shown and described herein a preferred embodiment of my invention, it is to be understood that 1 do not limit the application of my invention thereto, and any change or changes may be made in the structure arrangement of the parts within the spirit of the invention and the scope of the subjoined claims.

Now, therefore, I claim:

1. An apparatus for mixing, transferring and spraying a cementitious coating material, comprising in combination,

a. a power source,

b. hydraulic pump means connected to said power source,

c. air pump compressor means having first hydraulic-motoractuating means,

(1. mixing means having second hydraulic-motor-actuating means,

e. transferring means having third hydraulic-motor-actuating means,

f. a hydraulic fluid carrying circuitry including bypass solenoid valve control circuitry interconnecting said hydraulic pump means with said first, second and third hydraulic motors,

g. noale means for spraying said coating material,

h. conduit means arranged between said air pump, said transfer means and said nozzle means for supplying said nonle with said coating material output and said air pump compressor means output, and

. switching means on said nozzle means electrically connected to said solenoid valve control circuitry for controlling operation of said transfer means.

2. The apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 1 wherein said hydraulic fluid carrying circuitry comprises a first circuit connecting in a continuous loop said hydraulic pump means with said first hydraulic motor, a second circuit connecting in a continuous loop said hydraulic pump means with said second hydraulic motor and a third circuit connecting in a continuous loop said hydraulic pump means with said third hydraulic motor, and wherein said solenoid valve control circuitry comprises a pair of valves electrically controlled and arranged in opposite operating closed vs. open position for assuring continuous hydraulic fluid circulation through part of said circuitry at all times via one of said solenoid valves.

3. An apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 2 wherein said nozzle means for spraying said coating material carries an air valve and a coating material supply valve in addition to said switching means thereon.

4. An apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 3 wherein said first circuit connecting in a continuous loop said hydraulic pump means with said first hydraulic motor for driving said air pump has incorporated therein a bypass valve for regulating pressure of hydraulic fluid in said first circuit and for controlling speed of said first hydraulic motor, and indicating means connected to said bypass valve for determining required hydraulic fluid pressure in said first circuit by adjusting said bypass valve.

5. An apparatusfor mixing, transferring and spraying a cementitious coating material as claimed in claim 4 where said second circuit and said third circuit continuous loop is provided with a bypass relief valve and indicating meter means for controlling said hydraulic fluid pressure in said second circuit and said third circuit and for regulating said second and said third hydraulic motor actuating means output.

6. An apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 5 wherein said hydraulic fluid carrying circuitry including said bypass solenoid valve control circuitry is connected to said hydraulic pump means via a hydraulic fluid supply tank.

7. The apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 6 wherein said power source comprises an internal combustion engine including transmission and shifting means for engaging said power source with said hydraulic pump means.

8. The method for preparing and applying a cementitious wall and ceiling coating mixture, comprising the steps of:

a. actuating a power source for engagement with a hydraulic P p b. opening valve means for actuating a hydraulic motor for from the mixer to the nozzle e. manually opening at and mixture valves on the nozzle for spraying material from the nozzle and f. electrically switching the flip-flop solenoid valve arrangement by the nozzle switch for stopping the spraying procedure when required.

9. An apparatus for mixing, transferring and spraying a cementitious wall coating and ceiling material comprising in combination:

a. a power source,

b. a hydraulic pump connected to said power source,

0. an air pump compressor having a first hydraulic motor,

d. a dual mixing tank having a second hydraulic motor for rotating wiper blades in said dual tank first tank section for mixing a ceiling material and for rotating wiper blades in said second tank section for mixing a wall-coating material,

. a first transferring stator tube connected to said first tank for pumping the wall coating material towards a wallspraying nozzle,

a second transferring stator tube connected to said second tank for pumping the ceiling material towards a ceilingspraying nozzle,

. a conduit for delivering air connected between said air pump and said wall-spraying nozzle and connected between said air pump and said ceiling spraying noale,

h. a third and a fourth hydraulic motor connected to said first stator tube and said second stator tube, respectively, for operating said first and second stator tube,

. a hydraulic fluid-carrying circuitry including a bypass solenoid valve control circuitry interconnecting said hydraulic pump with said first, second, third and fourth hydraulic motors,

j. said bypass solenoid valve control circuitry comprising a pair of valves electrically controlled and arranged in opposite operating closed versus open position with one another for assuring continuous hydraulic fluid circulation through part of said circuitry at all times via one of said solenoid valves when said hydraulic pump is operating, and

k. switching means on each of said nozzle means for electrically operating said solenoid valves in said solenoid bypass circuitry for controlling operation of said stator tubes.

10. The apparatus for mixing, transferring and spraying a cementitious wall coating and ceiling material as claimed in claim 9 wherein said hydraulic fluid circuitry serving said air pump is provided with a bypass valve and pressure indicator circuitry for regulating hydraulic fluid pressure and consequently output of said air pump by regulation of said bypass valve, and wherein said hydraulic circuitry serving said mixing tank and said stator tube third and fourth hydraulic motors is provided with a bypass relief valve and indicator short circuitry for relieving pressure and for regulating performance of said mixing tanks and stator tubes so that said nozzle material output quantity can be regulated. 

1. An apparatus for mixing, transferring and spraying a cementitious coating material, comprising in combination, a. a power source, b. hydraulic pump means connected to said power source, c. air pump compressor means having first hydraulic-motoractuating means, d. mixing means having second hydraulic-motor-actuating means, e. transferring means having third hydraulic-motor-actuating means, f. a hydraulic fluid carrying circuitry including bypass solenoid valve control circuitry interconnecting said hydraulic pump means with said first, second and third hydraulic motors, g. nozzle means for spraying said coating material, h. conduit means arranged between said air pump, said transfer means and said nozzle means for supplying said nozzle with said coating material output and said air pump compressor means output, and i. switching means on said nozzle means electrically connected to said solenoid valve control circuitry for controlling operation of said transfer means.
 2. The apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 1 wherein said hydraulic fluid carrying circuitry comprises a first circuit connecting in a continuous loop said hydraulic pump means with said first hydraulic motor, a second circuit connecting in a continuous loop said hydraulic pump means with said second hydraulic motor and a third circuit connecting in a continuous loop said hydraulic pump means with said third hydraulic motor, and wherein said solenoid valve control circuitry comprises a pair of valves electrically controlled and arranged in opposite operating closed vs. open position for assuring continuous hydraulic fluid circulation through part of said circuitry at all times via one of said solenoid valves.
 3. An apparatus for mixing, transferring and spraying a cementitious coating maTerial as claimed in claim 2 wherein said nozzle means for spraying said coating material carries an air valve and a coating material supply valve in addition to said switching means thereon.
 4. An apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 3 wherein said first circuit connecting in a continuous loop said hydraulic pump means with said first hydraulic motor for driving said air pump has incorporated therein a bypass valve for regulating pressure of hydraulic fluid in said first circuit and for controlling speed of said first hydraulic motor, and indicating means connected to said bypass valve for determining required hydraulic fluid pressure in said first circuit by adjusting said bypass valve.
 5. An apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 4 where said second circuit and said third circuit continuous loop is provided with a bypass relief valve and indicating meter means for controlling said hydraulic fluid pressure in said second circuit and said third circuit and for regulating said second and said third hydraulic motor actuating means output.
 6. An apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 5 wherein said hydraulic fluid carrying circuitry including said bypass solenoid valve control circuitry is connected to said hydraulic pump means via a hydraulic fluid supply tank.
 7. The apparatus for mixing, transferring and spraying a cementitious coating material as claimed in claim 6 wherein said power source comprises an internal combustion engine including transmission and shifting means for engaging said power source with said hydraulic pump means.
 8. The method for preparing and applying a cementitious wall and ceiling coating mixture, comprising the steps of: a. actuating a power source for engagement with a hydraulic pump, b. opening valve means for actuating a hydraulic motor for operating a mixer containing wall and/or ceiling cementitious coating materials, c. opening a valve for actuating a second hydraulic motor for operating an air pump for supplying air to a spray nozzle, d. electrically switching a flip-flop solenoid valve arrangement in the hydraulic circuitry for actuating a third motor for operating a stator tube pump for transferring mixture from the mixer to the nozzle, e. manually opening air and mixture valves on the nozzle for spraying material from the nozzle and f. electrically switching the flip-flop solenoid valve arrangement by the nozzle switch for stopping the spraying procedure when required.
 9. An apparatus for mixing, transferring and spraying a cementitious wall coating and ceiling material comprising in combination: a. a power source, b. a hydraulic pump connected to said power source, c. an air pump compressor having a first hydraulic motor, d. a dual mixing tank having a second hydraulic motor for rotating wiper blades in said dual tank first tank section for mixing a ceiling material and for rotating wiper blades in said second tank section for mixing a wall-coating material, e. a first transferring stator tube connected to said first tank for pumping the wall coating material towards a wall-spraying nozzle, f. a second transferring stator tube connected to said second tank for pumping the ceiling material towards a ceiling-spraying nozzle, g. a conduit for delivering air connected between said air pump and said wall-spraying nozzle and connected between said air pump and said ceiling spraying nozzle, h. a third and a fourth hydraulic motor connected to said first stator tube and said second stator tube, respectively, for operating said first and second stator tube, i. a hydraulic fluid-carrying circuitry including a bypass solenoid valve control circuitry interconnecting said hydraulic pump with said first, second, third and fourth hydraulic motors, j. said bypass solenOid valve control circuitry comprising a pair of valves electrically controlled and arranged in opposite operating closed versus open position with one another for assuring continuous hydraulic fluid circulation through part of said circuitry at all times via one of said solenoid valves when said hydraulic pump is operating, and k. switching means on each of said nozzle means for electrically operating said solenoid valves in said solenoid bypass circuitry for controlling operation of said stator tubes.
 10. The apparatus for mixing, transferring and spraying a cementitious wall coating and ceiling material as claimed in claim 9 wherein said hydraulic fluid circuitry serving said air pump is provided with a bypass valve and pressure indicator circuitry for regulating hydraulic fluid pressure and consequently output of said air pump by regulation of said bypass valve, and wherein said hydraulic circuitry serving said mixing tank and said stator tube third and fourth hydraulic motors is provided with a bypass relief valve and indicator short circuitry for relieving pressure and for regulating performance of said mixing tanks and stator tubes so that said nozzle material output quantity can be regulated. 